I can really sympathize, as I'm having the same problem! Though I don't need to worry about working for the man, I'm a stay at home mum and the little man sure needs plenty of my time!
I think what you said about just focusing on a task until it's done, each time, is a good idea- that's what I'm trying to do, as I find one of my big problems is that I'm always thinking of the ten other things I need to do while I'm doing any given thing, and it's hard to concentrate, go quickly, and do a good job sometimes.
I think a part of this is just a time factor- getting used to everything, giving yourself a chance to settle into a routine that works personally for you. I'm trying not to be too strict with myself, as I know that doesn't work for me and I end up just having to throw a set schedule away after a day or two.
Rather than make a complete schedule, therefore, I try to give myself one priority for each day- for example, my priority for today is to work on a commission from a friend of mine. Everything feels less overwhelming if I focus on one definite goal at a time, and then I can feel like I've accomplished something when (or if!) I manage it.
I'd say, give yourself time and find an approach that fits your own style and personality.
(Sorry if I've rabbited on too much!)